“I kind of figured that that’s what was going on,” says Sharon on part two of a two-part Dr. Philairing Thursday. She says she’s devastated after years of trying to help her daughter.

“Heroin addicts wear their families down. They give to them, and they give to them, and they give, and they give - whenever they don’t even have to give to themselves, but they’ll give whatever they could give to them, try and help them. And one day you’re just, just like, ‘I am so tired of this. I can’t help her.’ I will shout it from the rooftops: ‘I cannot help her.’”

What does Sharon tell Dr. Phil she believes led Niki to start abusing drugs? This episode airs Thursday.